The Gunbuster video is a bit on the grainy side, but thats to be expected with its age. Mind you I don't have an HD TV so, but it sill looks good through component.
As for the extras, the first is a press event featuring cast & crew about the release. The next is a doc about the making of & new recording sessions. T he third is the trailer, & the last is audio spots & an audio "what if" Nono & Noriko met. But that is the untranslated stuff.